1. Field of the invention
This invention generally relates to yarn dyeing machines, and, more particularly, to a device for charging and discharging yarn cheeses from cheese frames.
2. Description of the prior art
As is known, for dyeing yarns, cheeses on which yarns are wound are used and these cheeses are arranged at a cheese frame which has on its center a support post and a number of hollow columns having radial holes, on which the cheeses are threaded and stacked so as to form cheese stacks. When the cheese frame is filled, it is lifted and inserted in the dye liquor container where the yarn is dyed by flowing the dye liquor through the column holes and the holes which the inner wall of the cheeses are provided with, from the outside to the inside and viceversa.
The charging and discharging operations of the cheeses on the cheese frames are carried out by hand or by means of devices provided with three arms angularly spaced by 120.degree., which place the cheeses on the columns and then the cheeses stacks in rows. However, since the cheese frame is normally circular in shape, a row arrangement of the cheese does not give the possibility of best utilizing the cheese frame surface, resulting in a dye liquor waste.
Therefore, the present trend is to provide cheese frames which can utilise the greatest portion of their surface. In order to attain this object, the cheese stacks are arranged in concentric circles and the cheeses of each circle are offset to those of the adjacent internal or external circle. By means of a cheese frame of this kind, the cheeses are nearly in contact to each other and the void spaces among the cheeses are practically reduced to a minimum. In the known devices, therefore, the cheese charging and discharging operations cannot be carried out because the above mentioned charging and discharging elements can no longer accurately enter the spaces among the cheese stacks, since these spaces are circumferentially spaced in an irregular manner charging and discharging yarn cheeses from cheese frames of dyeing machines, yarn cheeses, which overcomes the above mentioned drawbacks and which lends itself to charge and discharge the cheeses in a fully automatic manner without intervention of labour.